Electric dehydrator



' Mai-ch 1936- T. N. ST. HlLL- ELECTRIC DEHYDRATOR Original Filed Aug.19, 1932 [NM-M17226, WHO/v46 /V. 62 604,4

Hrroervsx Patented Mar. 10, 1936 UNITED STATES PATENT QFFIE ELEo'rmoDEHYDRATOR fornia Application August 19, 1932, Serial No. 629,412Renewed July It, 1935 '1 Claims.

My invention relates to the'electric treatment of petroleum emulsions,and more particularly to an improved type of electric treater. I

Petroleum as it comes from the well is often associated with minutewater droplets and forms a relatively tight water-in-oil emulsion.Before this petroleum can be used commercially the water content must bematerially reduced. In

the past, 011 refineries have considered a reduc- 10 tion in watercontent to below 3% to be satisfactory, but pipe-line. requirements ofmany refiner-lies now call for oil having no more than a traction of 1%of water therein.

Many types of existing electric dehydrators will not meet such pipe-linerequirements, and it is an important object of the present invention toprovide a new type of electric treater utilizing a dual field and whichis very effective in removing substantially allof the water from.petroleum emulsion. a

it is a further object of the invention to provide a treater having aplurality of treating spaces, and to impress a higher potential acrosscertain oi these treating spaces than across certain other of thesespaces whereby the emulsion is subjected to successively higherpotentials.

It is a further object of the invention to pro vide a novel electrodestructure, and preferably to rnalre one portion of this electrodestructure rotatable.

Another object of the invention is to provide a novel emulsionintroduction system.

Still further objects and advantages of the invention will be madeevident to those skilled in the art iromthe following descriptions ofthe preferred embodiment of the invention.

in the drawing-- Fig. l is a vertical sectional view illustrating tlnedetails of the preferred form oi? the inver1- tion.

Fig. 2 is a sectional viewtaken on the line 2-2 oi Fig. l.

Referring particularly to Fig. l, l have illustrated a tank iiiincluding upper and lower heads ii and it, this tank being substantiallyfilled with liquid. An intake means it extends into the lower end of thetank and is in the form of an intake pipe including an upward extendingleg it. A plurality of nozzles l extend outward from an intermediatesection of this leg and coinmunicate with the interior thereof. Varioustypes of nozzles may be utilized, but in the preierred embodiment itutilize four pipes suitably secured to the leg is and extending outwardtoward the tents. The outermost ends of these pipes are bent so as todischarge nonradially with respect to the tank. It is usually preferableto bend the ends of the pipe, as .best shown in Fig. 2, so that inefiect they discharge in a direction tangential to a circle around theaxis of the leg l5. In addition, it is preferable to bend the outer endsof these pipes slightly upward'so that they discharge in an inclineddirection. Emulsion is forced under pressure through the intake means i4 and is forced through the nozzles l1, being discharged non-radially soas to set the body of liquid in the tank "I into circulation. The upwardinclination of the ends of these nozzles serves to give the incomingemulsion an upward movement so that it rises in the tank it. Anysuitable means may be provided for closing the upper end of the leg it.In Fig. l a plug it is shown in this capacity. I The upper end of theleg t forms a central electrode 2 and may be enlarged as shown. In otherinstances such an enlarged electrode is not necessary and this electrodemay be oi the same diameter as the lower portion of the leg 5.

An insulator it is supported by the upper head .l inside the tank andcarries a bearing it of the thrust type which in turn rotatably supportsa rod ll. An intermediate electrode it is hired to the lower end oi therod ll so'as to rotate therewith, and comprises a ilat interstitialelec= trode ii preferably formed of screen suitably re== iniorced sothat it is maintained in a horizontal position. The intermediateelectrode til also in cludes an electrode means in the form of a plu=rality of blades or arms t2 depending therefrom and extending betweenthe central electrode ti and the tank. A lower treating space is thusformed between the central electrode 2 and the depending arms 32, andanother treating space is formed between the lower portionoi the fiatinterstitial electrode ti and the upper end oi. the electrode iii. Thesetreating spaces have been termed primary or lower treating spaces andrespectively indicated by the numerals Jill and lid Additional treatingspaces are formed between the blades and the tank it as indicated by thenumeral lit, while the edge of the fiat interstitial electrode illcooperates with the tanlr iii in defining still another treating spaceindicated by the numeral ti.

The final treating action tslses place in an upper treating space formedbetween the iiat interstitial electrode it and an upper interstitialelectrode ill providing a central opening ll through which the rod 2?extends. insulators 43 and 44 support this upper interstitial electrode40 and insulate it from the tank.

It is preferable to establish a potential difference between theelectrodes 30 and 40 which is greater than the potential differencebetween the electrodes 2| and 30. This may be accomplished by any one ofa number of means. In Fig. l, I have shown a pair of transformers 48 and49 providing secondary windings 50 and 5|, one terminal of each beingconnected together and to the tank In as by a conductor 52. Theremaining terminal of the secondary winding 50 is connected by aconductor 53 to the upper live electrode 40 through the insulator 44,while the remaining terminal of the secondary winding Si is connected bya conductor 55 to the intermediate electrode, a bushing 58 beingprovided to carry the current through the upper head H. The primarywindings of these transformers are connected to a supply line 52. Thetransformers are connected in additive relation so that the potentialbetween the fiat interstitial electrode 3! and the upper electrode 40will be represented by the sum of the potentials developed by thesecondary windings 50 and 5|. On the other hand, the potentialdifference between the tank HI and either the electrode 30 or 40 is muchless than this additive potential, being the potential of only one ofthe secondary windings. In view of the fact that the electrode 2| iselectrically connected to the tank l0, it will be clear that thepotentials across, the lower treating spaces 34 and 35 will also be lessthan the'potential across the upper treating space 38.

In the operation of the device the tank I!) may be preliminarily filledwith dry oil. The incoming emulsion discharged from the nozzles I! willset this body of oil into rotation and the emulsion will rise in thetank and into the treating spaces 34, 35, and 36 wherein it will besubjected to an electric field corresponding in magnitude to thepotential developed by the secondary winding 5i. In these treatingspaces the water droplets of the emulsion are acted upon by the electricfield and coalesce into larger masses. Most of these larger masses willdrop downward from these treating spaces and into the lower end of thetank M where they will form a body of water which can be removed fromthe tank through a pipe 80. The remaining emulsion constituents moveupward in the tank and either move through a more intense field set upin the treating space 31 adjacent the edge of the fiat interstitialelectrode 3l or move upward through the interstices of the interstitialelectrode 3| and thence into the treating space 38. Here the remainingemulsion is subjected to a still more intense electric field and furthercoalescence is eifected, the water droplets moving downward through theinterstitial electrode 3] while the dry oil moves upward through theinterstitial electrode 40 and is withdrawn from the upper end of thetank through a pipe 8|.

The tendency oi the emulsion to form low resistance paths between theelectrodes defining the treating spaces is counteracted by twotendencies. In thefirst place, it will be clear that the rotation of theliquid in the tank In rotates the intermediate electrode 30 at a speedwhich is only slightly less than the speed of rotation of the liquid inthe tank. The arms 32 are preferably shaped in the form of flat plates,as shown in Fig. 2, to increase the force tending to turn the electrode30. In the second place, any tendency to form low resistance paths acoss the treating spaces is minimized by the use of potential sourcesconnected as s wn in conjunction with an upper treating space into whichonly the drier emulsion moves, this drier emulsion having much lesstendency to short-circuit the electrodes than the original wet emulsionintroduced through the nozzles H. In addition, leakage currents areminimized by the electrode system shown, for the potential between thetank I0 and either the electrode 30 or electrode 40 is only half thepotential eifective in treating the emulsion in the upper treating space38.

Such a dual-field system is effective in removing the greater percentageof the water from the emulsion, so that the oil moving through the pipe6| has a water content which is only a fraction of 1%. One of theimportant features of the invention is the use of superimposed fieldsthe uppermost of which is of higher potential. Another feature of theinvention is the particular electrode structure utilized, and especiallythe interstitial construction thereof which permits liquid to reach theupper treating space 38 through the interstices thereof. Still anotherfeature of the invention is the novel construction of the distributingmeans including the nozzles ll, especially in conjunction with thecentral electrode 2! which is supported thereby.

- I claim as my invention:

1. In an electric treater, the combination of: a tank; an intermediatelive electrode in said tank but insulated therefrom and including a fiatinterstitial electrode; a live upper electrode above said intermediatelive electrode and insulated from said tank, said upper and intermediatelive electrodes cooperating in bounding an unobstructed upper treatingspace in which an electric field may be established of a maximumpotential determined by theidiiference in potential of said liveelectrodes; electrode means below said fiat interstitial electrode andcooperating with said intermediate live electrode in defining a lowertreating space communicating with said upper treating space through theinterstices of said fiat interstitial electrode; and potentialsupplymeans electrically connected to said upper and intermediate liveelectrodes and to said lower electrode means and including a pair oftransformer windings connected in additive relation for building upbetween said upper and intermediate live electrodes -bounding said uppertreating space a high potential, one of said transformer windings beingconnected between said lower and said intermediate electrodes to estab--lish therebetween alower potential.

2. In an electric treater, the combination of: a tank; an intermediatelive electrode in said tank but insulated therefrom and providing a fiatinterstitial electrode and a downward extending electrode meansdepending from said flat interstitial electrode; an upper live electrodeabove said intermediate live electrode and insulated from said tank andfrom said intermediate electrode, said upper and intermediate electrodescooperating in bounding an unobstructed upper treating space in which anelectric field may be established of a maximum potential determined bythe difference in potential of said live electrodes; a lower electrodecooperating with said downward extending electrode means to de fine alower treating space communicating with said upper treating spacethrough the interstices of said flat interstitial electrode; means forintroducing the emulsion to be treated into said lower treating spacewhereby a portion thereof flows upward into said upper treating space;and means for establishing fields in said treating spaces comprising apotential-supply means impressing between said upper and intermediateelectrodes bounding said upper treating space a potential difierencegreater than between said lower electrode and said downward extendingelectrode means.

3. In an electric treater, the combination 0!: a pair of electrodesspaced from each other and electrically connected together; anintermediateelectrode extending into the space between the electrodes ofsaid pairand insulated therefrom, said pair of electrodes cooperatingwith said intermediate electrode in defining a primary treating space;an upper electrode above and insulated from said intermediate electrodeand cooperating therewith in defining an unobstructed secondary treatingspace in which an electric field may be established oi-a maximumpotential determined by the difference in potential or said upper andintermediate electrodes and which secondary treating space communicateswith the material moving upward from said primary treating space; andmeans for establishing a potential difference between said upper andintermediate said tank; a central electrode extending into the spacebounded by said intermediate electrode and in spaced relationship withsaid arms and -said flat interstitial member to'deflne a treating space;

means for rotating said liquid in said tank whereby said intermediateelectrode is turned by contact with said rotating liquid; and means forestablishing an electric fleld between said centralelectrode and saidintermediate electrode whereby the liquid is treated and a portionthereor rises through said flat interstitial member to the upper portionoi. sa id tank.

5. In an electric treater, the combination of: an intake pipe providinga leg in the form of a pipe; nozzle means communicating with said leg atan intermediate section between the upper and lower ends thereof, theendof said leg beyond said nozzle means comprisir eiectrode; means forclosing said intake pipe at asection above said nozzle means; means forsupp 1 1 emulsion to be treated to said intake pipe whence it isdischarged from said leg through said nozzle means; electrode meansaround said electrode formed by said leg and cooperating therewith indefining a treating space supplied with emulsion by said nozzles; andmeans for establig a potential diiIerence across said treating space.

6; In an electric treater, the combination of: a tank containing a bodyof liquid; an intake pipe providing a leg; a rotatable electrodesurrounding said leg, the terminal end oi said leg forming an electrodecooperating-with said rotatable electrode in defining a treating space;nozzle means supported by said leg and communicating with anintermediate section thereof, said nozzle means supplying emulsion tosaid treating space and being directed non-radially with respect to saidtank to set said body of liquid into rotation whereby said rotatableelectrode is rotated; and means for establishing a potential diiIerencebetween said electrodes to set up an electric field in said treatingspace.

7. In an electric treater, thecombination of: a tank containing a bodyof liquid; an upper interstitial electrode providing a central opening;means for insulating said upper electrode from said tank; a rodextending through said central opening to a point therebelow; anintermediate electrode secured to said rod and previding a flatinterstitial electrode with a plurality.

of arms depending therefrom, said flat interstitial electrodecooperating with said upper interstitial electrode to provide an uppertreating space; an intake pipe extending upward in said tank inalignment'with said rod, the upper end or said intake pipe providing acentral electrode elec- 1 arms are positioned between said centralelectrode and said tank; nozzle means extending into said tank andintroducing the emulsion to be treated therein, said nozzle means beingdirected non-radially with respect to said tank to set said liquid intorotation; means cooperating with said rod for rotatably mounting saidintermediate electrode whereby this electrode moves with said rotatingbody or liquid; and means for establish- 'ing a potential differencebetween said upper andintermedlate electrodes and between said tank andsaid upper and intermediate electrodes.

THOMAS N. s'r. HILL.

jrically connected to said tank, whereby said lllli lid

